Vacuum-tight seal



Jan. 1, 1929.

W. DALLENBACH VACUUM TIGHT SEAL Filed Oqt. so, 1925 Iz'pvefih t N.Doll/e11, kac u 59% K W Patented Jan. 1, i929. UNITED STATES WALTERDALLEN BACH, OF ZURICH, SWITZERLAND, ASSIGNOR TO AKTIENGESELL- SCHAFTBROWN, BOVERI AND VACUUM-TIGHT SEAL.

CIR, OE BADEN, SWITZERLAND.

Application fled October ao,192s, Serial no. 671,802, and in cermanNovember 3, 1922.

The most satisfactory packing forjoints for sleeve-insulators forleading electrodes through the walls of metal vessels containing avacuum (more particularly for leading-in the anodes in mercury vapourrectifiers) has been found to be a combination of a layer of asbestoswith a mercury seal super sed on it: Various other packings have ailedin practice for reasons which vary with the various materials used.

The present invention has forits object to I provide an improvedvacuum-tight joint which is at least equal in efiicacyto the provedmercury and asbestos joint ab e referred to 115 and attains variousadditional advantages.

An essential feature of this improved joint for sleeve-insulators forelectrodes is that suitably shaped metallic members are cemented to thesleeve insulator at the places where the packing material is introduced.

A constructional example of this invention is'illustrated in theaccompanying drawing which is an axial section of the improved jointapplied to the Lease of an insulating and vacuum tight sleeve-insulatorfor an anode of a mercuryvapour rectifier. According to thisconstruction, as shown, the insulator i has cemented to it' at the twojointing places, joint members in the form of metal rings 6 and c whichserve'as centering guides and supporting means for the insulator and theanode a. The arrangement is as follows The anode is fitted by means of abearing fillet e and a fixed collar 0! into the ring a, whilst thering?) fits with its base and its outer edge exactly in an annulargroove formed in the rectifier vessel or cover At both jointing placesthere is provid above the rings 6 and a respectively a narrowcylindrical an- 40 nula-r space for the reception 0.1.5 thepacking.

This packing is composed of a pliable packing it of asbestos, lead wool,lead cord, or the like and a liquidseal f. This sealing liquidmay bemercury, provided the packing h is a non-metal (for instance asbestos),and the rings 6 and c are made of a metal (for instance iron) that willnot amalgamate. To avoid such limitations, the sealingliqui-d f mayconsist of viscoussubstances having low vapour pressure and suchviscidity that even when heated to the ordinary working tem peraturesthey will not exude through the pores or interstices of the acking, suchas for nstance a softcOmpoun such as picein, oil

' as varnish, &c.

The-construction of the packings h and f is such as to ensure avacuum-tight closure of the' actual jointproper between the ring a andthe anode a as well as between the ring b and the wall 9 of the vessel,and also the cemented joint between the ring I; or the ring 0 and theinsulator i.

For the purpose of catching any sealingv liquid that may leak through orrun off in the dismantling of the apparatus, gutters m and n areprovided underneath the packed joints, which gutters can be removed andemptied and also cleaned out when the electrode is dismounted. r Withthe object of cooling and protecting the anode a from silent discharges,the said anode enclosed, so as to leave a narrow ace between the two, ina metal jacket k-w ich may be screwed in the wall of the vessel.

What I claim is 1. An insulating joint for electrical apparatuscomprising the combination with a vessel provided with a seat portion,of an insulator for accommodating an element'to be in sulated from thevessel, and metallic joint members aflixed to the insulator and formedfor contact respectively with the seat portion and said element, saidjoint members forming the sole connections between the insulator andsaid other parts.

2. Electrical apparatus comprising the combination with a vesselaffording a seat portion and an element to be insulated therefrom, of aninsulator .for accommodatin passage of said element into the vessel, an

metallic joint members afiixed to the insuanother metallic joint memberafiixed to the insulator and formed for fitting contact with the seatportion, whereby the insulator is supported on the latter.

4. An insulating joint for electrical apparatus comprising thecombination with a sealed vessel having a seat portion and an e1ement tobe insulated therefrom, of an insulator formed to accommodate passage ofthe element into the vessel, a metallic joint member affixed to theinsulator and formed to make a centering fit on the element, and anothermetallic joint member aflixed to the insulator and formed to make acentering fit on the seat portion.

5. An insulating joint for electrical apparatus comprising thecombination with a sealed vessel having a seat portion and an element tobeinsulated therefrom, of an insulating bushing having a longitudinalbore for accommodating said element, a metallic joint member aflixed tothe bushing and extending into its bore, said joint member being formedto make a supporting and encompassing fit on the element, and a secondjoint member aflixed to the bushing and formed to make a centering fiton the seat portion.

' 6. An insulating seal for electrical apparatus comprising thecombination with a sealed vessel and an element to be insulatedtherefrom, of an insulator formed to accommodate passage of the elementintovthe vessel, a metallic joint member affixed to the insulator andhaving a close fit against the element, a second joint member affixed tothe insulator and having a close fitagainst a portion of the vessel, andsealing material covering the joints between said joint members and theother aforementioned parts.

7. An insulating seal for electrical apparatus comprising thecombination with a sealed vessel and an element to be insulatedtherefrom, of an insulator formed to accommodate passage of the elementinto the vessel, a metallic joint member carried on the insulator andhaving close fit with peripheral and overhanging surface ortions of theelement, a second metallic oint member connected to the insulator andhaving close fit with angularly related surface portions of the vessel,and liquid material covering the joints between the contacting portionsof the joint members and said other parts.

8. Electrical apparatus as specified in claim 2, together with sealingliquid covering the joints between said joint members and the parts incontact therewith, and gutters arranged to receive sealing liquidseeping through said joints.

9. Electrical apparatus as specified in claim 2, together with sealingliquid covering the joints between said joint members and the parts incontact therewith, and gutters communicatin with said joints.

In testimony w ereof I have signed my name to this specification.

WALTER DALLENBACH.

